High pitched pulse

[SWW]

Using the Digi CoreAudio I'm getting a high pitched pulse whenever I turn any audio app on (including Pro Tools 7.3.1)

Anyone have any clues about how to stop this?

Mac OS X.4.8 on MacBook Pro (Original MBox via USB)

[SWW]

(high-pitched pulsing sound is still there after updating firmware)

[The Dougfather]

The only time i have a high pitched whine is when i leave the Pre's cranked right up and forget to turn them back down.

Cheers

[SWW]

Even with the pre's all the way down, the high-pitched pulse is still there..

[OddsAre]

just a thought, but do you have a Bluetooth wireless mouse running too. I have heard it messes things up sometimes. I have been running a Bluetooth wireless mouse and keyboard for 6 months with no issues. Some people have had problems... Also just for the heck of it try other ports on the computer, and then if you know anyone with LE installed on their computer try it an see if it happens on theirs... and try their hardware on yours. if it still screws up on their computer and theirs works fine on yours then it may be time for an Mbox2...

[SWW]

Interesting post!

In my case no bluetooth devices at all.

[The Dougfather]

You may have a ground loop, something thats pretty hard to isolate, i purchased an Asus notebook a little while back and had to return due to a real loud noise when launching the Mbox. You could look at some sort of grounding device. I took a look at the Behringer site the other night and they have an inline device which balances the signal, it may be the problem.

Cheers

Berhringer Hum Destroyer

[SWW]

hmm.. I am using Berhinger speakers. I'll look into the ground loop issue. Although not sure why this would be suddenly happening since upgrading to new computer (MacBook Pro)